IOT | 3Way Switch Without Current Meter Auto Calibrating | Alexa | NodeMcu | Tutorial #18

In this tutorial you will learn how to control a 3 way switch with Alexa without using a current meter. This project can be done with ESP8266 and NodeMcu.
Project Source Code at GitHub
github.com/nas...
Tutorial # 15
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[@roystervi]

Hi and thanks for the video I just flash it to my nodemcu and it working great... Question, I ask before... is there a way to control this via http url?? the nodemcu ip address is "192.168.0.182" ... I am looking a way to turn on the switch via a url command again thanks in advance

[@netmedias7657]

bobby royster Thanks for trying it out. I will update the code and post it to GitHub once I have some free time.

[@roystervi]

When you do a update can you please tag me on the code can you please tag my name so I can be notify?

[@davidmoran4471]

Nice idea using the diode-resistor to feed the analog in. If the 1/4W resistor was getting warm that would indicate a significant current flow. Wouldn't tapping off from a voltage divider with higher value resistance be a better idea? You could also set the voltage divider to make wider range for AC input. You have another viewer below asking about 230V if you set the divider to give 0.25V for 115/120V then you would have ≈ 0.5V for 230V main power, which is well within the 8266's 1.0V maximum input on A0.

[@netmedias7657]

David Moran You are right and your are one of the best viewers I have bar none. I did not have to use my brain today to answer some of the questions. You took care of them and thank you for that. 😊

[@mkhumbie5484]

David hi, I am trying to understand the circuitry of the current reading through A0. Unfortunately, I am failing to get my fingers around it. This is what I see. I see two 3 way switches (mechanical relay & a switch) connected back to back with mains power on the common side of the switch and the common of the relay connected to both the load and the diode (in fwd bias) and the diode with the protect resistor of 47kOhms to A0. My question is how is A0 reading any current through? what voltage is it using? When say both switches are allowing current through from mains the load will complete the circuit, cool! the current will also flow thru the diode in fwd biased state BUT not complete the circuit as it is open end through A0 right?? how then do we calculate current through that protecting resistor which I believe is the one we are reading through A0? Please I understand the basics of electronics diodes and voltage divider circuits but I can't see past this. I know it works, here at RSA we are on 230 Mains and I want to implement this...

[@tiwar87]

Netmedias , i did it but i can't calibrate good the System! I don't understand how the ac voltaje is converted in DC to go at A0 pin. I measure with the voltemer and it said 50v that was going to the input A0, i know it wasnt real voltaje! Where can I learn about it or how can I set up the System for a wide range of different loads? Thanks

[@pedrohenriquepeixoto3964]

+David Moran Do you mind elaborating on that? Is this voltage divider like a potentiometer? Electronics is not my forte, so I'm having a hard time following it.

[@BTopbas]

​@@netmedias7657 So which parts needs to works with 220-230v ac main?

[@roystervi]

again thanks for the videos and each time I can say I learn something new... keep up the good works

[@netmedias7657]

bobby royster Thanks

[@willrnsantana]

WOW!! Simply the perfect solution. Thank you SO MUCH!

[@tiwar87]

Thanks buddie, great idea to replace the current meter, ! Keep going forward..

[@netmedias7657]

tiwar87 Thanks

[@pluckygalaxy]

Excellent tutorial! Thank you for making this!

[@netmedias7657]

pluckygalaxy Thank you for your feedback.

[@nitishprajapati4060]

Thanks for making this type of videos

[@netmedias7657]

Thank you.

[@ccasadog]

Hi, I don’t have knowledge on electronics, electricity nor programming but I’ve been able to do this tutorial. :) Thank you for making it ease. I’m interested in a 4 way switch so the MCU is in the middle and in case it crashes, I can still turn the light on/off from the two manual switch. I understand that a dpdt relay is needed for this. It would be great if you can do a tutorial about this. Greetings from Spain.

[@netmedias7657]

Cristobal Casado thank you for your valuable feedback. Stay tuned for more variations for 3 and 4 way switches.

[@fasihzafar7423]

i dont have any alexa devices. i want to use this method with blynk application. will you please help me out ,how to do that.

[@wayneperryman4146]

I also am after the same thing.

[@sayedhussaini4894]

I also please help me out I want to use this using blynk

[@ashwin6970]

HI Bro .. i have been watching your videos for the last two days , and trying to understand the things which u have done to connect the three way switch with the single relay ..later but i understood the connection shown in the diagram .. i have not gon the coding part . but i will watch the coding part later . .. other thing is that i dont have much knowledge like you do in electronics components and circuit connections , but just know little bit of this and that .. well coming to the point here .. i have echo dot , a both 4 channel and a 8 channel relay . also have successfully connected to the echo dot and relays with the help of nodemcu esp8266 .. till now haven't fired it up on the ac mains .. but i used with the dc currents to switch on and off all the relays with the help of alexa .. but i havent connected using the three way switch just like liked you shown in the video with dc current , as well as with the ac current too . next thing is that i i wanted to connect it with the ac power .. just like you shown . i was planning for my room automation after seeing your video with the ac current connected with relay and alexa with three way switch . but in the diagram you are connected to only single relay and also connect to a analog input . so here you want to help me out . i dont know what to do with it , as per i wanted to connect a 4 channel relay , (or a 8 channel relay with the help of nodemcu in future ) . also how to connect the analog pin too if using a ( 4 channel or a 8 channel relay' output loads) . so could you do a video how to over come with this situation , showing me how to connect the nodemcu esp8266 + 4 or 8 channel relay + along with ( how to connect the analog pin as input for the 4 channels or 8 channels relay as load ) . hope you will help me out in this .

[@kaivalyaahir5758]

hi bro you got any solutions???? i have same situation

[@maadhurdhananiwala6546]

hey how do I add more different lights and switches to control the light and even commands to Alexa

[@alfalotfi]

Please sir i'm waiting for 8 channel relay tutorial.

[@brunogonzalez6812]

Great way to substitute the current meter, just one question, is calibartion need to be done every time we reset it or in case of an electricity failure ?

[@netmedias7657]

bruno gonzalez You only need to recalibrate if you change the bulb with different power consumption. In case of power failure it does not lose the setting

[@prod8592]

Nice videos, I would like to do this project, is way more cheaper than buying a smart switch and you learn about iot, can you make a video in an actual wall and also with a power from the mains. Thanks

[@greyhnd001]

I really like this and I would like to see it done with micropython. It's easy to install on the esp8266. Micropython is 10 times easier to code as well.

[@netmedias7657]

Sour coming soon.

[@vladpuha]

Thank you for all you work and tutorials. They are great! I have 2 questions: I understand that A0 input is the only serial pin and you can connect one devise to A0 then do the job. Is it possible to have a setup to convert the current into digital output and then connect it to a data pin. Signal is present then devise is on. 2. Is it possible to have the setup you presented on solid state relay with 2 poles. thank you for your tuts they are easy to follow and reproduce!

[@netmedias7657]

Vlad Puha I am working on to find a way to leverage digital pins. You will need 2 solid stat relays to do the same setup. I will be doing a tutorial on this soon.

[@vladpuha]

thank you for the clue, Nassir! I will try to figure it out to if I can understand it. As for the analog to digital can a analog to digital be used? (I do programming for leaving dont have knowledge besides beyond basis in the field).

[@netmedias7657]

Theoretically, it should work.

[@marcosyllades8549]

Hi Nassir, thanks for the greats projects!! I have an issue with Alexa recognizing this device. On serial screen: Saving Calibrating current... 27 Reading EEPROM Door Status: 22 Reading Calibrating current... 22 Saving Calibrating current... 1024 Reading EEPROM Door Status: 1019 Any tougths? Regards.

[@netmedias7657]

Are you able to discover the device?

[@marcosyllades8549]

Not yet

[@marcosyllades8549]

@@netmedias7657 Hi there, Thanks for your response. Alexa finally detects the device but it says that "Demo switch is nos compatible with this". I had this error first at compiling: exit status 1 request for member 'indexOf' in 'request', which is of non-class type 'int' I comment those lines and it compiles but it doesn´t work as it should. Every time that I turn off the interruptor it keeps turning on by itself!!! 0########## Responding to /upnp/control/basicevent1 ... ########## Got Turn on request turnOnRelay..... 0 The effective value of the current is(in mA) 1024 Switch was on 0########## Responding to /upnp/control/basicevent1 ... ########## Got Turn on request turnOnRelay..... 0 The effective value of the current is(in mA) 156 Switch was off 0########## Responding to /upnp/control/basicevent1 ... ########## Got Turn on request turnOnRelay..... 1 The effective value of the current is(in mA) 1024 Switch was on Any ideas? Thanks in advance.

[@ganeshmurukutla8977]

Marcos Yllades i am also getting thr same error have u resolved it sir ??

[@rosspower7514]

Thank you for a great video. I am having trouble when the nodemcu is powered from an ac/dc converter. when connected, there is not enough difference in the threshold to detect the current. When powered from a battery source it is fine. any ideas on how to isolate the power supply or stop the feedback?

[@netmedias7657]

Ross Power I used the ac/dc adopter during the demo and it is working fine.

[@bradzimmerman306]

Hi. I'm just getting started in the Arduino world, and really like your tutorials on home automation. I have run into an issue with getting any of your sketches to work. They flash fine. My network recognizes them. I have used the Nodemcu, and the 8266 12E alone. I cannot get Alexa to control them. I get the message waiting for Belkin International, and "device is unresponsive" on my Alexa App. I turn the 8266 on and off thru Alexa and with the Alexa App, and get the same error messages. Sometimes it turns on, most of the time it doesn't. What Does Belkin have to do with the sketch? Also, the light is usually on- on the Nodemcu..Please help

[@johnefthymiadis302]

Good job the think is how is going to work on 4 relays and 4 separate loads?

[@netmedias7657]

Stay tuned. 8 channel tutorial coming soon.

[@sanjaykumarsinha3058]

That was a huge help! But can you please give us a Blynk compatible code for the same. It will be very helpful. I have got some other codes but they use current meter. And i don't know what changes would i have to make in their code.

[@deepachavali2424]

what about fail safe state of the circut.? like power down/ Internet down issues.?

[@Morfoz13]

Great project!! Is there a way how to replace the commands from Alexa to phone app or http? Thank you in advance!

[@Tgrossman96]

Im getting compiling error Arduino: 1.8.16 (Windows 10), Board: "Generic ESP8266 Module, 80 MHz, Flash, Disabled (new aborts on oom), Disabled, All SSL ciphers (most compatible), 32KB cache + 32KB IRAM (balanced), Use pgm_read macros for IRAM/PROGMEM, dtr (aka nodemcu), 26 MHz, 40MHz, DOUT (compatible), 1MB (FS:64KB OTA:~470KB), 2, nonos-sdk 2.2.1+100 (190703), v2 Lower Memory, Disabled, None, Only Sketch, 115200" C:\Users\Admin\Documents\Arduino\IOT-3Way-Switch-Without_Curent-Meter-Auto-Calibrating.ino\IOT-3Way-Switch-Without_Curent-Meter-Auto-Calibrating.ino.ino: In lambda function: IOT-3Way-Switch-Without_Curent-Meter-Auto-Calibrating.ino:232:14: error: request for member 'indexOf' in 'request', which is of non-class type 'int' 232 | if(request.indexOf("GetBinaryState") >= 0) { | ^~~~~~~ exit status 1 request for member 'indexOf' in 'request', which is of non-class type 'int' This report would have more information with "Show verbose output during compilation" option enabled in File -> Preferences.

[@hansjansen1961]

In the schematics in the video the cathode of the diode is pointing to the HV side. But further on in the video the cathode is pointing in the opposite direction. Why?

[@netmedias7657]

Hans Jansen I am not sure if this is the case then I may have made a mistake. Just follow the demo.

[@capextechnicalservicesllc3054]

hi it is a great video tutorial. can you please help me , how to add MQTT in this program so that i can connect it with home assistant.

[@hassanahmad9597]

what happen if you takeout the led and then turn it on

[@netmedias7657]

I am not sure what your are asking. It only works when the current is flowing.

[@nimeshlad594]

Sir can we make two control using normal SPST switch and relay using some code logic with node MCU ??

[@kenprochaska2286]

Is there a way to power up the MCU or 8266 from the mains? I would like to make a self contained unit with no outside power supply.

[@netmedias7657]

Ken Prochaska You can use the 110v to 3/5 dc Step Down Buck Converter. They are 3rd the size of MCU. www.ebay.com/itm/1PCS-5W-AC-DC-12V-450mA-Power-Supply-Buck-Converter-Step-Down-Module/191981585009?hash=item2cb2fe8271:g:9LUAAOSwYIxX4QL1 www.ebay.com/itm/1pcs-HLK-PM01-AC-DC-220V-to-5V-Step-Down-Power-Supply-Module-Household-Switch/152825646956?epid=874404704&hash=item23951e4f6c:g:WxcAAOSwh1haJOyT

[@amargupta.8847]

Netmedias , can we use any led driver and a 7805 to power the 8266, I think it's cheaper than other sources in my country...... By the way u deserve a great appreciation for ur effort... keep going man....

[@netmedias7657]

You can use any power supply that can provide 3.3 volts and at least 170 mA.

[@pongpolc.8696]

Thank you for your work. it is very cool. Does Node mcu work with google home mini. Many thank in advance

[@netmedias7657]

Pongpol C. Thank you.

[@seancunningham6785]

I am having an issue where the off command will both turn the relay high then Low, however the On command will do nothing as to changing the relay state . It's almost as if there is always current but I tested with a multimeter and there is none when light is off

[@netmedias7657]

It is doing that because the current sensing limit is not set correctly or you are using an Active low relay.

[@maadhurdhananiwala6546]

hey the project is too good and I was trying the code to verify in ide but the error is showing down below: Arduino: 1.8.9 (Windows Store 1.8.21.0) (Windows 10), Board: "NodeMCU 1.0 (ESP-12E Module), 80 MHz, Flash, Disabled, All SSL ciphers (most compatible), 4M (no SPIFFS), v2 Lower Memory, Disabled, None, Sketch + WiFi Settings, 115200" C:\Users\maadh\OneDrive\Desktop\3 way switch\IOT-3Way-Switch-Without_Current-Meter-Auto-Calibrating-master\IOT-3Way-Switch-Without_Curent-Meter-Auto-Calibrating\IOT-3Way-Switch-Without_Curent-Meter-Auto-Calibrating.ino: In lambda function: IOT-3Way-Switch-Without_Curent-Meter-Auto-Calibrating:232:14: error: request for member 'indexOf' in 'request', which is of non-class type 'int' if(request.indexOf("GetBinaryState") >= 0) { ^ exit status 1 request for member 'indexOf' in 'request', which is of non-class type 'int' This report would have more information with "Show verbose output during compilation" option enabled in File -> Preferences. ;

[@tanmaymondal885]

why this diode and resister are connected to the a0 port of nodemcu?

[@shouryasaha65]

Is it possible to use more than 1 relay? What about I use a 4 relay board? I think the real question is can there be more than 1 input pin for the diode+resistor?

[@netmedias7657]

Yes, but you need more than one analog pin.NodeMcu has only one. Use ADC converter to control more relay. Watch my Pi3 video. I am working on Sonoff 4 ch pro to make it current sensing without analog pins. Stay Tuned. kzbin.info/www/bejne/pnPblnuiq6tnm7M

[@amiromaramir7049]

Hi engr Nasir Malik i was making these days home project i wanna use relay with 2 way switch and 47k resistor is must or i can use other resistor .help me please

[@netmedias7657]

You need 47k or above

[@ahellard74]

Hi I was wondering what the code would look like if you just used a opto-isolator and just measured a high or low on the status pin?

[@netmedias7657]

Remove the "currentMeter();" in on off function in ino file and check the opto high or low and set the of "deviceState" void turnOffRelay() { Serial.println("turnOffRelay....."); Serial.println(digitalRead(relayPin)); // check opto state and set the deviceState variable to high or low Serial.print(digitalRead(relayPin)); if (deviceState == 1){ digitalWrite(relayPin, !digitalRead(relayPin)); // turn off relay with voltage LOW } }

[@ahellard74]

new to programming do I need to still have the current_meter .h file? @@netmedias7657

[@netmedias7657]

@@ahellard74 NO you don't need it. Remove it from your main sketch. Good Luck

[@bhutchins1991]

could you possibly post a link to the libraries you use, just to be sure as there are so many variations! thanks

[@netmedias7657]

github.com/nassir-malik/IOT-3Way-Switch-Without_Current-Meter-Auto-Calibrating

[@roystervi]

any dodemcu will work ???.. I know the older notemcu does not have the VV, also I have a switch I like to try this on. the switch is control from two different location.

[@netmedias7657]

bobby royster It will work any ESP8266 and NodeMcu.

[@SebiMT301]

Could you show please how can I do the same directly with raspberry pi? I am working on a smart home solution and my problem is the relay is working with switch but separately and the relay doesn't recognize if I turn my switch. Thank you!

[@netmedias7657]

I'll upload a tutorial soon.

[@krishnpalsinghchouhankp]

Is it possible add 4 or 8 relay and check power

[@dipankarsarkar0503]

Can u make a light and ac dimmer with the same 3 way controlling then i can use the light or fan manually or by app?

[@netmedias7657]

Sure, stay tuned

[@markdav13s1]

Great video. Is there a way to use the same setup or the setup with power meter to run 2 separate switches to separate relays? And set it so if one relay is on the other relay turns off and vice versa? I'm looking to switch the fan speed between speed one and two with automation with also a backup manual switch. So when I set speed one on the fan speed two switches off. And same thing happens when speed two is selected. This tutorial would definitely help to get one speed going but I need tthe second speed also. They can't both be on at the same time because of the resistance difference on both switches. Hope someone can help.

[@netmedias7657]

Using this method has limitations since NodeMcu has only one analog pin. You can use converter but it makes it more complected. I show how to use ADC in pi 3 tutorial. I am working on another tutorial that works with that standard GPIO. Stay tuned.

[@markdav13s1]

Thanks for your reply. What if digital switches were used?

[@netmedias7657]

You can used ADC converter to use with digital pin.

[@aliasaad1347]

i want to use this wonderful method with 8 channel relay , can be done?

[@netmedias7657]

Yes, you can

[@priyeshsahani]

Hey i want to do this with the BOLT IOT KIT. How can i do so please help

[@arunsharmasp]

Can I use ACS712 (Current Sensor Module 20A range ACS712 Module module ACS712T Arduino) instead of this diode & resister???

[@netmedias7657]

Yes you can.

[@muthushankar9543]

hello there, when i try to upload the code i get this error.can somebody help to fix this issue IOT-3Way-Switch-Without_Curent-Meter-Auto-Calibrating:232:14: error: request for member 'indexOf' in 'request', which is of non-class type 'int' if(request.indexOf("GetBinaryState") >= 0) { ^ exit status 1 request for member 'indexOf' in 'request', which is of non-class type 'int'

[@ajaygupta-pj8qh]

Please make video for 8 or 4 CH relay circuit

[@netmedias7657]

Working on it. Stay tuned.

[@ericpeter2055]

the nodemcu can control upto 9 relays as it has 9 digital pins. Is there a way i could use a switch for all the 9 relays?

[@netmedias7657]

Use optocoupler/isolator to detect the current and then you can use all GPIOs. Good luck

[@Theo12415]

When is the 8 relay video coming out ?

[@randisetiawan9789]

Would you made same project like this but using the blynk app?

[@netmedias7657]

Sure. Stay tuned

[@randisetiawan9789]

I will wait for it, i have already search for project like this but i couldn't find it

[@randisetiawan9789]

I still waiting sir

[@eserviceconsultancy9466]

Hi if we want to use the same concept in tasmota sonoff firmware , will it work ?

[@netmedias7657]

It will not work as is. You will have to modify the tasmota code for this to work.

[@vanderleisilvasantos5343]

Can you make this with 4 relay?

[@roystervi]

Hi again... I re-flash the notemcu and have the diode and the resistor pointing accordingly... however, I can only get the light to turn off/off from alexa if the switch is in the on position. I can't seem to get the switch to turn on or off/off the light only if the relay is in the close position. My setup is just like yours along with the nodemcu v3 1########## Responding to /upnp/control/basicevent1 ... ########## Got Turn on request turnOnRelay..... 0 The effective value of the current is(in mA) 10 Switch was off 0########## Responding to /upnp/control/basicevent1 ... ##########

[@netmedias7657]

bobby royster You need to turn on the light and press the flash button to calibrate it.

[@roystervi]

When I say alexa turn off sw it will turn it off and when I say alexa turn off sw it will turn on 1########## Responding to /upnp/control/basicevent1 ... ########## Got Turn off request turnOffRelay..... 1 The effective value of the current is(in mA) 6 Switch was on 1Saving Calibrating current... 0 Reading EEPROM Door Status: -5

[@roystervi]

I think I find the problem .... My light switch (LSW) has the black screw where you hook up the two wire going to the relay.... so I connected mines just like you did. upon watch your video over and over the black screw have to go to one wire coming from the lamp. now its working Also, I have to put in a number here ........................."int device_on_current_threshold;//if the current value (100) is greater than this amount then the device is on" so I put 100 since off is 10 and I gave myself some leeway, I replace milliamps to (100).. now its working like it should... doing it this way I was about to use a url command......... "192.168.0.133/switch" turn the light off.........but I have no way to turn it back on via url command...

[@vladpuha]

you connected the pols on the switch wrong or on the relay. check again the tuts and your connection

[@yogeshitaliya473]

It's possible use multiple relay with A0 ? For example. 4 chenal relay us all connection A0

[@netmedias7657]

Yogesh Italiya No, You need one analog pin for each relay.

[@yogeshitaliya473]

@@netmedias7657 thankyou for reply

[@Amirt1999]

you cau use multiplexer

[@amargupta.8847]

Hey can I use the same diode for 230v supply.... and looks like even a simple mistake can burn the nodemcu.....

[@thegeekahub7663]

AMAR GUPTA. Same dought.

[@netmedias7657]

AMAR GUPTA/The Geekahub Please see the answer by "David Moran" above. Thanks for your comments.

[@maadhurdhananiwala6546]

i am not able to connect alexa to the esp266

[@YoshiFan190]

Hey, can i use the same resistor and diode for 220v systems?

[@netmedias7657]

Yes

[@chi-tinhnguyen5176]

What a nice video I have a question that How can we sercure data, if someonce also have alexa and they discover and they control our device... How can we encode that Please help me

[@netmedias7657]

Chi-Tinh Nguyen Use "WiFiClientSecure" for client instead. You can also use proxy with ssl for server.

[@chi-tinhnguyen5176]

Thank sir Please tell me that How can I do like you show me above

[@sayedhussaini4894]

Which terminal of the diode we have to connect to the line wire ?

[@netmedias7657]

Anode to wire and cathode to NodeMcu analog pin

[@RandomFunwithfact]

sir i m having a raspberry pi 3 and my plan is to make a smart house using esp2866 12 e i want to plac raspbeery pi in one room and rest al esp2866 12 e will but in whole house many relay will be connect to them i want to control them by smarhone as well as laptop as well as using voice what should i use can u plzz help me

[@netmedias7657]

Aniket I am doing the siiler thing. I want to use pi with touch screen as hub in few rooms and control everything from it. I will be doing a tutorial where you are able to connect and control multiple RF and wifi devices like ESP8266 and Rf radio. Stay tuned.

[@RandomFunwithfact]

thanks:)

[@ghigginbotham6095]

If I have more than one location can I do the same thing, but change location name in the code?

[@netmedias7657]

There is only one analog pin on NodeMcu. You have two options. First option is to use ADC converter as I show in following video or wait for next video that show how to do this without analog pin. kzbin.info/www/bejne/pnPblnuiq6tnm7M

[@roystervi]

Can MQTT be added to this code ? ... I was wonder if I can use something else other than alexa to turn the light on/off as well via mqtt

[@netmedias7657]

bobby royster You can add MQTT and URL support. I am doing URL trigger on/off in some of the projects.

[@roystervi]

does your IOT | 3Way Switch and your IOT | 4Way Switch has URL trigger on/off ... I have not install as yet

[@roystervi]

what is the URL command to trigger on/off

[@smcengineer6595]

Great Project. is there any way to use multiple relay control using ESP32 ...

[@netmedias7657]

Yes, See my other tutorial to control multiple relays. For current sensation you will need to use ADC converter if you want to support multiple current sensing devices.

[@smcengineer6595]

can we use ESP32 instead of ADC Converter and also want to control it using my smart phone, i am new to NODEMCU Prograaming....

[@Little_Shivya]

Really liked it.. Can this work with Google home??

[@netmedias7657]

I will upload a tutorial for Google Home soon. Stay tuned.

[@Roaming_with_akshay]

@@netmedias7657 please tell how to do it

[@giraftw2002]

why no transistor is required to drive the relay? please advise.

[@netmedias7657]

Mark Huang I am not sure I understand your question.

[@thegeekahub7663]

We want a sketch of 8 channel relay.

[@netmedias7657]

The Geekahub This buffet has a long line so you have to wait for your turn :-). Sir, your request is on my to do list. Stay tuned.

[@krishnpalsinghchouhankp]

Please Link your all video in next video

[@andreamitchell4758]

the problem is that you are not showing us how to wire it to a 3 way switch setup if you have one 3 way switch then you most likely have another 3 way switch that it goes to this is just showing how to wire the node MCU to the circuit with only one 3 way wall switch i have two 3 way wall switches and i want to use the node mcu and either of the 2 wall switches to control the light so can you pleas ed o video tutorial on how to wire it that way? i see you have both of the traveler wires going to the relay so then how would you connect in the other 3 way wall switch?

[@davidmoran4471]

His relay is the second 3 way switch. 2 wall switches and the node mcu control would require one of the wall switches to be a 4 way. The string of switches starts (power end) and ends (load end) with a 3 way switch and the additional switch(es) in the center of the string will all be 4 way switches. look at his IOT | Home Automation with Alexa | 4 way switch Part 3| and you will see it.

[@andreamitchell4758]

but that tutorial shows 3 wall switches and the node MCU smart switch i do not want that either i want 2 wall switches and the node MCU controlling the light , so what do i need and how do i wire it? one 3 way and one 4 way switch then take the neutral wire from the 4 way switch that goes to the light and put it on the com terminal of the relay and then connect the other 2 relay terminals to the 4 way switch traveler wire contacts?

[@andreamitchell4758]

one more issue i see is hw are we going to power the node MCU ? if i want to put this in my wall then can i use a 5v wall wart or maybe a buck converter to power the node MCU but then if you have a 3 way or 4 way switch you won't have one wire that is constantly hot

[@netmedias7657]

Andrea Mitchell Please see the "David Moran" answer. He is spot on. I am not sure if I can add anything to his answer. Good luck.

[@netmedias7657]

David Moran Thank you for your help. You did a better job explaining it than could have done.

[@girolamonicoletti4625]

Scusa non riesco a trovare il modulo con Alexa. Ciao Grazie

[@rushi5778]

How to add multiple switches????

[@rhendytay06]

Hi sir, can i change the resistor to 1/4 watt? If can then need to change the value in arduino code ? Nice tutor... Thanks.

[@netmedias7657]

It is risky. It may heat up and cause problems.

[@rhendytay06]

can i use a resistor 1/4 watt combine ? how many watt the lamp you using sir ? Thanks.

[@netmedias7657]

Rhendy Tay you can try to use the 1/4 watt resistor. If it stays cool then you are fine. If it starts to get warm then you will need the 1/2. I did the same thing.

[@rhendytay06]

Thank sir for your reply, get all working well.

[@bigdawg3600]

You are tapping off the 120 volt circuit to feed the GPIO on the micro controller? What about the common?

[@netmedias7657]

Eric Hughes I am not sure what your question is. Neutral wire is going directly from the plug to light bulb. Thank you for the feedback.

[@lelmus3277]

You are correct, the high voltage mains have no closed circuit to the ESP because the mains neutral is not connected to the ESP. What he’s doing is making an antenna that’s resonating very high due to the very high voltage and it’s getting picked up by the ADC in the ESP. Kind of similar concept to wirelessly detecting the engine running in a car. It’s not an orthodox design but could work. I probably would have done it very differently, but that’s just me.

[@netmedias7657]

Eugene Frenkel Thank you for your clarification I really appreciate it.

[@mkhumbie5484]

Hope I am not that late Eugene I have been trying to understand the circuit. So I have two questions what's the use of that 4.7k resistor then? 2. I see the circuit is not grounded but applying so much voltage across A0 will not affect the ESP?

[@netmedias7657]

Resistor is dropping the current down. My circuit is bear minimum. To protect the board you can use a fuse with correct amp power. Yes it works for 220 volts. You can test it with led first before your connect it to your board.

[@miguelelias8932]

Thank you so much for this tutorial, very interesting but for me doesn't work very good. i don't know what I did wrong, because when I say "Alexa, turn on demo switch" Alexa turn off the light, and when I say "Alexa, turn off demo switch" Alexa turn on the light. And sometimes doesn't work at all. Any Ideas????

[@netmedias7657]

Miguel Elias make sure calibrate it when light is on. Are you using Mechanical relay?

[@miguelelias8932]

Thank you for your quick response. Yes, I'm using the same relay you used on your tutorial. I tried to start it over deleting everything and flashing again, but everything got worse. Now i have errors. :(

[@miguelelias8932]

esptool v0.4.12 - (c) 2014 Ch. Klippel setting board to nodemcu setting baudrate from 115200 to 9600 setting port from to COM3 setting address from 0x00000000 to 0x00000000 espcomm_upload_file espcomm_upload_mem setting serial port timeouts to 1000 ms opening bootloader resetting board trying to connect flush start setting serial port timeouts to 1 ms setting serial port timeouts to 1000 ms flush complete espcomm_send_command: sending command header espcomm_send_command: sending command payload espcomm_send_command: receiving 36 bytes of data warning: espcomm_send_command: wrong direction/command: 0x00 0x08, expected 0x01 0x08 trying to connect flush start setting serial port timeouts to 1 ms setting serial port timeouts to 1000 ms flush complete espcomm_send_command: sending command header espcomm_send_command: sending command payload espcomm_send_command: receiving 36 bytes of data warning: espcomm_send_command: wrong direction/command: 0x00 0x08, expected 0x01 0x08 trying to connect flush start setting serial port timeouts to 1 ms setting serial port timeouts to 1000 ms flush complete espcomm_send_command: sending command header espcomm_send_command: sending command payload espcomm_send_command: receiving 36 bytes of data warning: espcomm_send_command: wrong direction/command: 0x00 0x08, expected 0x01 0x08 resetting board trying to connect flush start setting serial port timeouts to 1 ms setting serial port timeouts to 1000 ms flush complete espcomm_send_command: sending command header espcomm_send_command: sending command payload espcomm_send_command: receiving 36 bytes of data warning: espcomm_send_command: wrong direction/command: 0x00 0x08, expected 0x01 0x08 trying to connect flush start setting serial port timeouts to 1 ms setting serial port timeouts to 1000 ms flush complete espcomm_send_command: sending command header espcomm_send_command: sending command payload espcomm_send_command: receiving 36 bytes of data warning: espcomm_send_command: wrong direction/command: 0x00 0x08, expected 0x01 0x08 trying to connect flush start setting serial port timeouts to 1 ms setting serial port timeouts to 1000 ms flush complete espcomm_send_command: sending command header espcomm_send_command: sending command payload espcomm_send_command: receiving 36 bytes of data warning: espcomm_send_command: wrong direction/command: 0x00 0x08, expected 0x01 0x08 resetting board trying to connect flush start setting serial port timeouts to 1 ms setting serial port timeouts to 1000 ms flush complete espcomm_send_command: sending command header espcomm_send_command: sending command payload espcomm_send_command: receiving 36 bytes of data warning: espcomm_send_command: wrong direction/command: 0x00 0x08, expected 0x01 0x08 trying to connect flush start setting serial port timeouts to 1 ms setting serial port timeouts to 1000 ms flush complete espcomm_send_command: sending command header espcomm_send_command: sending command payload espcomm_send_command: receiving 36 bytes of data warning: espcomm_send_command: wrong direction/command: 0x00 0x08, expected 0x01 0x08 trying to connect flush start setting serial port timeouts to 1 ms setting serial port timeouts to 1000 ms flush complete espcomm_send_command: sending command header espcomm_send_command: sending command payload espcomm_send_command: receiving 36 bytes of data warning: espcomm_send_command: wrong direction/command: 0x00 0x08, expected 0x01 0x08 warning: espcomm_sync failed error: espcomm_open failed error: espcomm_upload_mem failed error: espcomm_upload_mem failed

[@miguelelias8932]

This is weird, (I change the name "demoswitch" for "Light"). Now is working but only saying "Alexa turn OFF the light" if the light was off turn it on, and if the light was on, turn it off, if I say " Alexa turn ON the light" Nothing happen, and Alexa replies OK. I can turn ON or OFF the light, only saying "Alexa turn OFF the light. Any Ideas how can I fix this??

[@capextechnicalservicesllc3054]

How to add MQTT broker in this

[@pedrohenriquepeixoto3964]

Is there . away to use one ESP8266 to make more than one 3-way switch?

[@netmedias7657]

Pedro Henrique Peixoto you can use ADC converter. I am trying to find a simpler way.

[@pedrohenriquepeixoto3964]

Netmedias didn't get where this converter would help. I though the bigger issue would be to dedetct the current from multiple switches, since the esp8266 only has one analog input

[@netmedias7657]

Converts analog to digital and you can check if GPIO high then device is on otherwise it is off.

[@nhatminh1209]

Could we use ESP-01 to do it without current meter?

[@netmedias7657]

nhatminh1209 No, since it does not have a analog gpio. You can use analog to digital converter with esp 01.

[@nhatminh1209]

Is digital converter too compicated :) I have fancy on creating like you. Can I ask you sometime with messenger?

[@vishaltejwani940]

How can i use it with ardunio nano and hc05 for time being?

[@netmedias7657]

Vishal Tejwani You will need some sort of wifi shield for nano for this setup to work. You can use the same sketch for nano just update the GPIO pin.

[@justineaaron333]

Hello, How to wire with multiple relay I want to measure four different loads using 4 relay module

[@netmedias7657]

Stay tuned for next tutorial for 8 relays.

[@himanshugore4427]

@@netmedias7657 Sir It's about 10 months when the next tutorial is coming.

[@netmedias7657]

@@himanshugore4427 Sorry for the delay. Next couple of weeks.

[@himanshugore4427]

Netmedias Ok Sir waiting for it.

[@vishalagarwal1451]

I wonder why dont you start your home automation startup you know to much about it??

[@netmedias7657]

You are right. Stay tuned.

[@JoCa_MPC]

Where you buy the relays ? they are 5v?

[@netmedias7657]

Jorge Capitão I get them from ebay for banggood. www.banggood.com/5Pcs-5V-Relay-5-12V-TTL-Signal-1-Channel-Module-High-Level-Expansion-Board-For-Arduino-p-1178210.html?rmmds=search&cur_warehouse=CN www.ebay.com/itm/1pc-DC12V-Channel-5V-Low-Level-Power-Supply-Relay-Module-SRD-12VDC-SL-C-Clips/311941401345?hash=item48a1280b01:g:RcMAAOSwxKtYBpYf

[@ahellard74]

Can this code be used on the same network on multiple esp8266s as long as the Device Name "DemoSwitch " is unique?

[@netmedias7657]

Yes

[@ahellard74]

Ok thanks I have seen people saying they have had issues with more than one device in the same lan.

[@ahellard74]

Netmedias when run the code it seems to work but if I use the Alexa app things don’t work correctly. Have you ever experienced that?

[@parimal67]

not able to discover device by alexa. can you help me out?

[@netmedias7657]

What do you see in Arduino serial window?

[@kaivalyaahir5758]

hi you did nice job but i have a issue what if i wanted to control 8 relays so can you tell me the code for that

[@netmedias7657]

Since there is one analog pin on NodeMcu we can only control one device. I am working on solution where you will be able to control using all GPIO pins.

[@kaivalyaahir5758]

@@netmedias7657 hi thanks for your reply i must appreciate it.and for that i have an idea and want to know that if it is possible or not because i am new at home automation.

[@kaivalyaahir5758]

@@netmedias7657 can we make a program with if else statement that if the relay is high than make it low and if the relay is low than make it high. for example:- if i say alexa turn on demoswitch than it will figure out that if the relay is high than make it low and it relay is low than make it high. so this way we don't need current sensor or anything else too. and we can control it from physical switch and alexa both... reply if it is possible or not....

[@justineaaron333]

is this possible with with arduino uno?

[@netmedias7657]

Justine Aaron Yes, you can use the same code and replace the timer code.

[@aliasaad1347]

can this method used with bylnk ?

[@netmedias7657]

Yes, just watch my bylnk tutorial

[@eagleeyegps8003]

how 8ch relay can we conect for this project??

[@netmedias7657]

Working on it. Stay tuned.

[@eagleeyegps8003]

okay

[@88TOPDOG]

Hi can this access via mobile phone APP

[@netmedias7657]

I will have mobile support in future support.

[@Roaming_with_akshay]

How to do same with Google assistant

[@netmedias7657]

Tutorial coming soon

[@hassanahmad9597]

Is it Work with adafruit?

[@netmedias7657]

It is Arduino compatible.

[@suchitaindulkar9822]

How to do this for 240V

[@netmedias7657]

Suchita Indulkar Set it up the same way just double the resistor value.

[@TheRebanein]

Can you tell me what diode you used? (newbie)

[@netmedias7657]

1n4007

[@SimoneGiacomelli]

You are awesome. Thank you for your great tutorial!

[@netmedias7657]

You're very welcome!